nfs4: Do not repeat OPENATTR requests if not supported

src/add-ons/kernel/file_systems/nfs4/FileSystem.cpp

@@ -27,6 +27,7 @@ FileSystem::FileSystem()
 	fPrev(NULL),
 	fOpenCount(0),
 	fOpenOwnerSequence(0),
+	fNamedAttrs(true),
 	fPath(NULL),
 	fRoot(NULL),
 	fId(1)

src/add-ons/kernel/file_systems/nfs4/FileSystem.h

@@ -62,6 +62,9 @@ public:
 	inline	uint32				OpenOwnerSequenceLock();
 	inline	void				OpenOwnerSequenceUnlock(uint32 sequence);
 
+	inline	bool				NamedAttrs();
+	inline	void				SetNamedAttrs(bool attrs);
+
 			FileSystem*			fNext;
 			FileSystem*			fPrev;
 private:
@@ -83,6 +86,7 @@ private:
 
 			uint32				fExpireType;
 			uint32				fSupAttrs[2];
+			bool				fNamedAttrs;
 
 			FileSystemId		fFsId;
 			const char*			fPath;
@@ -205,5 +209,19 @@ FileSystem::OpenOwnerSequenceUnlock(uint32 sequence)
 }
 
 
+inline bool
+FileSystem::NamedAttrs()
+{
+	return fNamedAttrs;
+}
+
+
+inline void
+FileSystem::SetNamedAttrs(bool attrs)
+{
+	fNamedAttrs = attrs;
+}
+
+
 #endif	// FILESYSTEM_H
 

src/add-ons/kernel/file_systems/nfs4/InodeDir.cpp

@@ -62,10 +62,16 @@ Inode::OpenAttrDir(OpenDirCookie* cookie)
 status_t
 Inode::LoadAttrDirHandle()
 {
+	if (!fFileSystem->NamedAttrs())
+		return B_UNSUPPORTED;
+
 	if (fInfo.fAttrDir.fSize == 0) {
 		FileHandle handle;
 
 		status_t result = NFS4Inode::OpenAttrDir(&handle);
+		if (result == B_UNSUPPORTED)
+			fFileSystem->SetNamedAttrs(false);
+
 		if (result != B_OK)
 			return result;